When loading and unloading bulk materials, especially coarse-grained or lumpy bulk materials, the surfaces of the machines that are in contact with these bulk materials are subject to especially intense frictional stress. These surfaces are therefore frequently protected with protective surfaces, so-called wear plates, against the stress.
A plurality of linings of dumping or transportation devices subject to abrasive stress are known from the state of the art.
Thus, U.S. Pat. No. 6,279,715 B1 discloses a mounting system for a chute, which mounting system has a framework carrying the chute, in which individual protective pads are hung. Recesses in the side edges of the wear plates snap in here behind snap-in elements. The wear plates may also be replaced individually. However, they must be pried out of the clamped connection by means of a tire lever for this. However, the edges and snap-in elements may become damaged when dumping in rocky material, which makes easy replacement impossible.
U.S. Pat. No. 5,055,336 A proposes that the bottom of a chute be provided with steel strips laid on edge, between which the wear plates are arranged detachably. The plates are bolted to the bottom of the chute. The bolts are arranged recessed in the wear plates and are covered by inserts, which protect the bolt heads. However, the cover may be expected to become damaged when filling rocky materials.
It is common in all documents mentioned that the wear plates are arranged on supports, from which they can be readily detached and replaced. However, it is remarkable that the interior space of the chutes must be entered when replacing the wear plates in order to bring the wear plates to the point at which they are to be fastened, because the fastening elements are to be loosened from the side of the wear plates. Since it is difficult to access these fastening elements and they may also be destroyed because of the mechanically rubbed-off particles and the contamination of these fastening elements, all the means disclosed for accomplishing the object have a problem in common.
U.S. Pat. No. 7,232,023 B2 is an exception. The wear plates are hung here at their upper edge into a mechanical holding device. Moreover, the wear plates are arranged in the manner of a slated roof, so that the row of plates arranged at a higher level protects the suspensions of the row arranged under it by partially overlapping this. However, it cannot be overlooked that this construction is suitable for lower stresses only, because a row of cavities, where the wear plates do not lie flatly on the support construction, is formed under the wear plates. In addition, despite the coverage by a superjacent row of wear plates, the holding devices are susceptible to mechanical stresses, which may lead to bending of the holding devices.
U.S. Pat. No. 3,883,080 A pertains to an arrangement of wear plates, which is designed as a lining of a surface that is subject to stress. Rubber or a similar substance is provided as the lining material. The lining is effected section by section, and the lining sections are held by self-threading bolts. The self-threading fastener meshes with the lining material. The projecting end of the bolt is passed through the supporting wall and locked with a nut. However, the lining sections obviously cannot be replaced without direct access to the lined surface.
The replacement of the wear plates must be performed from the stressed side in all construction variants according to the state of the art. The risk of material possibly falling from a storage hopper located at a higher level at the time of changing a plate cannot therefore be eliminated by these constructions.